Why is this useful?
In precommit: Pre-Commit Hooks

Why use pre-commit hooks?

Better commit quality = better code quality

The goal of pre-commit hooks is to improve the quality of commits. This is achieved by making sure your commits meet some (formal) requirements, e.g:

that they comply to a certain coding style (with the hook style-files).
that you commit derivatives such as README.md or .Rd files with their source instead of spreading them over multiple commits.
and so on.

Why use the pre-commit framework?

Using hooks from a framework like pre-commit.com has multiple benefits compared to using simple bash scripts locally in .git/hooks or use boilerplate code in other CI services to perform these tasks:

Focus on your code. Hooks are maintained, tested and documented outside of your repo, all you need a .pre-commit-config.yaml file to invoke them. No need to c/p hooks from one project to another or maintain boilerplate code.
A declarative configuration file for routine checks. File filtering for specific hooks, language version of hooks, when to trigger them (push, commit, merge), configuration options - all controlled via a single configuration file: .pre-commit-config.yaml.
Locally and remotely. Or just one of the two. You can use pre-commit locally and in the cloud with pre-commit.ci, where hooks can auto-fix issues like styling and push them back to GitHub. Exact same execution and configuration.
Dependency isolation. {precommit} leverages {renv} and hence ensures that anyone who uses the hooks uses the same version of the underlying tools, producing the same results, and does not touch your global R library or anything else unrelated to the hooks.
No git history convolution. Pre-commit detects problems before they enter your version control system, let's you fix them, or fixes them automatically.
The power of the crowd. Easily use hooks other people have created in bash, R, Python and other languages. There are a wealth of useful hooks available, most listed here. For example, check-added-large-files prevents you from committing big files, other hooks validate json or yaml files and so on.
Extensible.. You can write your own R code to run as a hook, very easily.
Standing on the shoulders of giants. Leveraging pre-commit.com drastically reduces complexity and abstracts away a lot of logic that is not R specific for the maintainers of {precommit}.
Independent. pre-commit is not bound to GitHub, but runs on your local computer upon commit, and pre-commit.ci will support on other git hosts than GitHub in the future.